Weather resistant covers are often employed to protect electrical devices, such as receptacles, plugs and connectors that are exposed to the harsh elements of weather, such as moisture, rain, snow, and the like. Weather resistant covers are often also used to protect electrical devices, such as receptacles, plugs and connectors, located indoors in industrial facilities, and the like, which can also experience high moisture conditions, such as when surfaces are sprayed or hosed down for cleaning, and which may be exposed to unwanted contaminants, such as dust.
Weather resistant covers can be used in conjunction with electrical boxes or other housings (collectively “boxes”) to protectively enclose a variety of electrical and/or optical (i.e., fiber optic) devices when one or more electrical wiring devices of the box are either in use or not in use. Such boxes often contain one or more electrical receptacles or connectors to which power cabling can be removably connected using a standard plug arrangement as is readily known by one of ordinary skill in the art. To gain access to the receptacle or connector the weather resistant cover can be opened or removed, such as by unlatching or unscrewing, and an electrical connection can be made to the electrical receptacle or connector via the plug. When the electrical connection is no longer required, the plug is removed and the cover is closed or reattached to the box, providing protection from moisture, weather and unwanted contaminants.
The National Electrical Manufacturers Association (NEMA) provides standards for protection provided by certain enclosure “types.” For example, a NEMA Type 3 enclosure must provide protection from ingress of water such as rain, sleet and snow. A NEMA Type 4 enclosure must provide protection from the ingress of water such as rain, sleet, snow, and in addition must provide protection against splashing water and hose directed water. A NEMA Type 12 enclosure must provide protection from the ingress of dirt, circulating dust, lint, fibers and flyings. The International Electrotechnical Commission (IEC) also provides standards for protection of enclosures. For example, an enclosure meeting the IEC's International Protection (IP) Code IP66 must provide complete protection from dust, oil and other non-corrosive material, as well as protection from powerful jets of water.
To comply with NEMA Type 4, Type 12, and/or IP66 requirements, some weather resistant covers include a threaded cap that mates with threads formed on the electrical box or connector so that the cap can be screwably coupled to the cover. Other weather resistant covers include a flip lid that is hinged to the box. The flip lid is pivotable between an open configuration to expose the electrical receptacle or connector, and a closed configuration when the electrical receptacle or connector is not in use. In some weather resistant covers, a gasket may be provided in the lid to engage a surface of the box to provide a seal therebetween. Because the lid often has a limited range of movement through which the gasket can be compressed, such arrangements may generally not be able to provide a desired degree of sealing (i.e., NEMA Type 3, Type 4, Type 12, or IP66). This is because the lid compresses the gasket via a swinging movement (and not a perfectly axial movement), and as such the gasket may be adequately compressed only on one side of the lid, and may not experience sufficient compression on the opposite side of the lid. Thus, with current flip-lids that are hinged to the box, a gap can be present between the lid and the gasket when the lid is in a closed position (i.e., when the lid covers the receptacle). As a result, under extreme conditions moisture or fluid can leak past the gasket on the side opposite the hinge. This effect can be magnified due to manufacturing tolerances. To combat this, hinged lid type covers often include an affirmative latch or locking mechanism that requires the user to press down on the lid to fully engage the gasket and lock the lid to the box.
As can be appreciated, problems exist with the aforementioned cover designs because they require affirmative user action in order to effect a weather resistant seal that complies with NEMA Type 3, Type 4, Type 12, and/or IP-66 requirements. With the threaded cap design it has been found that users often fail to re-attach (i.e., re-thread) the cap after using the receptacle or connector. With the flip lid design, it has been found that users may not re-latch the lid to adequately compress the gasket. In both instances the electrical connections may not be protected from the environment or may be limited to a NEMA Type 3 rating.
Accordingly, it would be desirable to provide a weather resistant cover having a sealing arrangement that results in a desired high degree of moisture and water resistance (e.g., complying with NEMA Type 4 and IP66) as well as dust protection (e.g., complying with NEMA Type 12) with minimal user action.